question?
Thread Starter
On The Tree
Joined: Jan 2007
Posts: 124
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question? hey i have a 97 trans am and my heater and ac **** is not working right. when i turn the **** on it only goes to the defrost. it doesnt go to the floor or a/c or regular vents. it only blows throw the defrost. what is the problem? any help? and i dont have a vacuum leak at all. i check all the vacuum lines and there are no cracks and the lines are good. help please. thank you
i would seek a local a/c shop too... 
Next to the PCM and evaporator there are a series of vacum lines that go into a small plastic thing. Have no idea what it's called. anyway they tend to crack and break off the barbs for the vac lines and it causes the vents to loose vacume control and it blows only out the defrost vent. check that first. It sounds like a vacume leak. Vac control valves don't go bad that often, it is usually a vac leak in a line that causes this.
